... ),same as 1/3 of clay brick and 1/5 common concrete.So use the Light brick can reduce the ... has many are porous ,the delivery hearting coefficient is 0.9-0.22W/(mk),the same as 1/4 or 1 ... /5 of clay brick ,so it is best materials now ... Ton coal ash ,and save coal ash using area 0.5 mu,save burning clay brick 5 mu . High quality Aerated autoclaved concrete block machines